Transcript for Officials on How Weapons Got into Webster, NY, Gunman's Hands

Thank you. As all know early Christmas Eve morning five days ago. West Webster volunteer fire fighters left their beds left their homes left their station. In order to respond. To a fire which was I'm going on lake road in Webster. Once firefighters are dry -- they were met by one -- Williams spangler. A convicted felon who had been released from new York state prison for manslaughter. Involving the killing. -- grandmother. Mr. spangler was armed with three weapons. And he proceeded to murder. To what Webster -- volunteer firefighters. Mike -- -- -- who was also a Webster police lieutenant. And also told -- Could shock and could. Could shoot cop who is a west and west Webster volunteer firefighter. Spangler -- -- wounded two other firefighters. -- hip -- Stadler. And Theodore star Dino. As they arrived to fight the fire. As is also already been reported. William Spain -- body was found that same day. Spangler had killed himself with a self inflicted gunshot wound. Located next to Spain lower were three firearms. To all of which. Wore a bushmaster. Two -- three rifle. And Hamas for twelve gauge shotgun. Today we are all here to one now it's the arrest. And the filing a formal charges. Against the person who purchased. That rifle and a shotgun -- next to Williams spangler. Specifically. We have today arrested dawn win. And GUYENH. 24. Who used to be the neighbor of spangler. On lake road in Webster. The precise charge against dawn win has to -- with lying. During her purchase. Of these two weapons. According to the publicly filed complaint. Dawn -- told the seller of these guns gander mountain located in Henrietta New York. -- she was to be the true owner and buyer of the guns. Instead of Williams spangler. It is absolutely. Against federal law to provide any materially. False information. Relating to the acquisition. Of firearms. Providing your own name when buying a firearm instead of the true owners name. Is sometimes referred to is acting as a straw purchaser. And -- is exactly. What today's complaint alleges. You see William spangler as a convicted felon could not legally own. Acquire. Purchase. Any firearms. Whatsoever. Congress specifically. Passed a law. Requiring people to provide the true owner. To precisely stop what spangler in -- did this past Christmas Eve. Now let me saying that this investigation. Is continuing. Two important. Next stall need to be mentioned before I turn this over to the special agent in charge of eight -- First. All of us that you see here stand shoulder to shoulder. And will continue to pursue. Any and all leads as to precisely. Who. And how all these firearms came into the possession. Of Williams spangler. Secondly. And perhaps most importantly. All of our thoughts and all of our prayers. Continue to -- to our fallen officers and their families and friends. They were specifically targeted murder and wounded. Because they were rushing to help others. And while William -- -- may have escaped the criminal justice system. Those who provided the firearms to spangler. Day he used -- Christmas Steve. To murder and wound -- firefighters. And the police officer. Will not escaped -- criminal justice system. I need to specifically. Fake. All of the hard work and dedication. Of the Webster. West Webster volunteer. Firefighters. The Webster police department. Of Monroe county sheriffs. To New York State Police. The district attorney's office here in Monroe County. And of course the federal Bureau of Alcohol, Tobacco, Firearms, and Explosives. Led by a special agent in charge -- and a -- all. Also this case will be handled. By the attorney in charge of the US attorney's Rochester branch. And that's Brett -- Jack. Who is in court with miss no -- And her attorney as we speak. With that I will turn it over to the special agent in charge to be followed by other comments and then certainly your questions. Think. Thank you bill. First off I would like to thank the United States attorney. Webster chief of police Monroe County district attorney Monroe County sheriff. West -- of fire department New York State Police. For allowing us allowing us to partner. With them in this investigation. In light of the tragic events that occurred on Christmas Eve. I would like to express my condolences. To the families of those affected in the community of Webster and Monroe County. ATF is the federal agency that focuses on violent crime and illegal use and possession of firearms by criminals. This includes targeting those who would unlawfully purchase firearms for criminals this is known as -- straw purchase. When a non prohibited person buys a firearm and -- gives it to prohibited person. And in some cases a person with serious criminal history stone as a straw purchase. As today's arrest and complaint alleged. Straw purchase -- -- was responsible for purchasing firearms. Used in the ambush of our fellow first responders. And public service. For that to be held accountable. ATF for the part -- enforcement agencies will continue to work. Together system they leave the -- firearms. These events have only strengthen our resolve. To work together to combat the scourge. Of gun violence that is plaguing so many of -- communities today. Good afternoon -- -- again thank you for being here. And before I start I would really like to commend this community for the outpour of support that you've shown during the past few days it is truly commendable. And I would also like to think in your state police and -- county sheriff's and Webster police department for all of they've done through this horrible tragedy. Now as mr. -- just told you miss Newman is being arraigned currently on federal charges but there'll also be a state counterpart. We are planning on filing at least at this point falsifying business records in the first degree which is a class. She will be arraigned in Henry Henrietta tempore and I'm not sure of the date that was given to -- by the New York State Police. So -- albeit -- prosecution on the state side however one thing that is really important for this community to know is that this is an ongoing investigation. And we are. You're speaking to further individuals in gathering more information four additional potential charges. Tim cross bearing -- the second assisting in the mineral county district attorney's office will be cross designated as assistant US attorney. To assist mr. hope on the prosecution of -- win on the federal side. So again thank you -- your support and thank you for being here.

This transcript has been automatically generated and may not be 100% accurate.

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